Self-adjusting plural blade cutting roller with cushioned anvil roller

ABSTRACT

A cylindrical cutting roller with plural cutters cooperating with a cylindrical anvil roller, in which the cutting roller has cutters arranged in rows on its cylindrical surface, said cutters having been self aligned with a setting plastic material, and the anvil roller comprising concentric deformable inner and hard outer sleeve elements along its length to cooperate with the rows of cutters on the cutting roller.

United States Patent [191 Ross [ SELF-ADJUSTING PLURAL BLADE CUTTING ROLLER WlTl-l CUSHIONED ANVIL ROLLER [75] Inventor: William C. Ross, Brooklyn, NY.

[73] Assignee: Consolidated Educational Publishing, Inc., Locust Valley,

[22] Filed: June 5, 1972 [21] Appl. No.: 259,988

[52] U.S. Cl 83/346, 83/348, 83/659, 83/665, 83/678, 83/698, 144/221 [51] Int. Cl 826d 1/56 [58] Field of Search 83/6, 12, 341, 346, 347, 83/348, 659, 660, 663, 665, 669, 692, 906,

. [56] References Cited UNITED STATES PATENTS I 546,565 9/1895 Turner 83/906 X 1 July 16, 1974 833,261 10/1906 Tardie 144/221 2,549,251 4/1951 3,119,312 l/1964 Henc 83/698 3,269,236 8/1966 Johnson et al.... 83/348 3,274,874 9/1966 Treiber et a1..... 83/348 3,289,513 12/1966 Johnson et a1 83/348 X Primary Examiner-Andrew R. Juhasz Assistant Examiner-W. D. Bray Attorney, Agent, or Firm-Edward Halle, Esq.

[57] ABSTRACT A cylindricalcutting roller with pluralcutters cooperating with a cylindrical anvil roller, in which the cutting roller has cutters arranged in rows on its cylindrical surface, said cutters having been self aligned with a setting plastic material, and the anvil roller comprising concentric deformable inner and hard outer sleeve elements along'its length to cooperate with the rows of cutters on the cutting roller.

25 Claims, 6 Drawing Figures mimimzsmn 3.8233533 FIG. 2

SELF-ADJUSTING PLURAL BLADE CUTTING ROLLER WITH CUSHIONED ANVIL ROLLER BRIEF SUMMARY OF THE INVENTION on the journals and bearings of the rollers, will be greatly reduced during the cutting cycle.

It is also an object of the invention to provide for the impact of the cutters against the anvil portion of the device successively.

It is another object' of this invention to provide a cutting and anvil roller arrangement in which there is n evermore than one blade of the cutting means cutting at a time.

It is a further object of the invention to provide for the cutting force to be exerted equally along different portions or sections of the length of the rollers, so that the cutters will each press with the same cutting force preventing overloading of any single cutter and destroying the sharp edge.

-It is another object of the invention to provide for a simple alignment of the plurality of cutters.

The various objects of the invention are accomplished by the device of the invention in which the plurality of cutters are arranged in staggered rows and the anvil is comprised of sleeves of flexible material and hard material as will be set forth hereinbelow. The simple cutter alignment is accomplished by providing cutter aligning or positioning means made of a setting plastic material as will be described hereinbelow.

DESCRIPTION OF THE DRAWINGS This invention is illustrated in the accompanying drawings in which:

FIG. I is a perspective view;

FIG. 2 is an end view with parts cut away;

FIG. 3 is a front elevational view with parts cut away;

FIG. 4 is a perspective view of a cutter of the invention;

FIG. 5 is an elevational view, partly in section, showing installation details of a cutter of the invention; and

FIG. 6 is a view similar to FIG. 4 showing another cutter of the invention.

Similar numerals refer tos'imilar parts throughout the several views.

DETAILED DESCRIPTION OF THE INVENTION In the drawings a cutting roller and an anvil roller 22 are illustrated. Reference numeral 24 represents a work piece such as a web of material, usually paper or the like, whichis to be worked by the device to provide cuts, such as cross cuts 28, and 32 at desired places on the web 24. The components for handling the web 24,andreeling it through the space 26 between the rollers 20 and 22 are well known in the art and not shown.

Dotted lines 34 and 36 are, provided in FIG. I to show that the web 24 may (in some subsequent operation) be slit along the dotted lines 34 and 36 to provide three ribbons of the web material having spaced cross cuts 28, 30 or 32, respectively. This is given by way of illustration only to show a use for the invention, it being understood that either roller of the invention can be used in other applications as desired.

In the preferred form of the device the cutters are placed on a roller 20 which is provided with journals 38. The cuttingroller 20 works in conjunction with an anvil roller 22 which is provided with journals 40. The journals 38 and 40 may be seated in appropriate journal bearings in a main frame (not shown) in any manner well known to the art so that the cutters are positioned to operate in conjunction with the anvil surface. In a preferred form of this invention it is not necessary to seat'the journals in aspring-type of bearing because of the system of cutter adjustment that will be described hereinbelow.

It is sufficient to understand the workings of the invention that roller 20 and roller 22 are positioned so that the cutters 42, 44 and 46, as well as all of the other cutters of the invention, are mounted on the cutting roller 20 so that their cutting edges 56 may be adjusted with relation to the surface 48 of the anvil 22. The cutter holders and adjustment means will be described further hereinbelow.

The web 24 is directed and reeled, by any reeling means known to the art, around roller 22 in the direction of arrow F as shown in FIG. 1 of the drawings. The web 24 will have cross cuts such as cuts 28, 30 and 32 worked into it when the edge 56 of a cutter, such as cutters 42,-44, 46, respectively, will be forced against the surface 48 of anvil roller 22 with web 24 between the cutter and the anvil. Every cutter of the invention effects its cut in the same manner. In the preferred form of the invention each cutter will operate singly once during each revolution of the cutting roller 20. Thisis accomplished by providing a systematic staggering of the cutters.

The dotted lines 50 in FIG. 3 is representative of an imaginary cylindrical surface in which the edges 56 of all of the cutters 42, 44, 46, etc. will substantially travel during rotation of the cutting'roller 20. Imaginary cylindrical surface 50 is comprised of an infinite number of elements, or lines, such as dotted line 52 which are parallel to axis 54 of the cutting, roller. As used herein the term element is a line within the surface of a cylinder and parallel to the axis of the cylinder.

Each cutting edge 56 of a cutter of the invention is contained in one of said imaginary parallel element lines 52 comprised in the imaginary cylinder surface 50. For-example, line 52 as illustrated in FIG. 3 of the drawings is coincident with edge 56 of cutter 46. Every other edge 56 of any cutter of the invention is also coincident with an imaginary parallel element, or line, of which line 52 is representative for all such elements within the surface of cylinder 50, parallel to its axis 54. Only one example is illustrated in order not to cover the drawings with a multitude of imaginary dotted lines which are unnecessary to a further understanding of the conception of the invention.

The cutters are arranged in circular rows as illustrated by dotted lines at reference numerals'60, 62 and 64 in FIG. 3. The dotted lines 60, 62 and 64 are described as circles since they form circles around the axis 54 of the roller 20.

Cutters such as series of cutters 42, 42a, 42b and 42c, spaced degrees apart (FIG. 2), are arranged along circle 60 (FIG. 3) Cutters 44, 44a, 44b and 440, also 90 degrees apart, but 30 degrees out of phase with the series 42 cutters, are arranged along circle 62. Cutters 46, 46a, 46b and 460 are positioned along circle 64, again 90 degrees apart, and also 30 degrees out of phase with the series 44 cutters. It will be noted that each series of cutters 42, 44 and 46 are 30 degrees out of phase with each of the other series. By creating this staggered arrangement no two or more cutters will make a cut at the same time. Only onecutter in the entire array of cutters'will make a cut at a time. This is because each cutter is coincident with only one of the infinite number of axially parallel lines 52.

While it is not absolutely necessary, in the preferred form of the invention the arrangement of the cutters is symmetrical. However, the cutters may be arranged in rows defined by circles and being spaced at any desired distance apart to form any cutting configuration on the web 24 so long as the force of the cutting operation is distributed by providing for a minimum cutting force, such as by providing for only one blade to operate at a time.

All of the cutters in the series 42, series 44 and series 46 are identical in the preferred form of the invention and unless there is some reason to distinguish one from the other, they will be referred to collectively under the numeral 42, 44, 46. The preferred cutter 42, 44, 46 is rectangular in'shape, preferrably square as shown in FIG. 4, so that'any one ofits eight edges 56 can be used for the cutting edge. The roller 20 is provided with cutter holding means, such as pockets, 66 which are positioned in the body of the roller 20 so as to present a flat side 68 against which the cutter 42, 44, 46 (see 46a in FIG. 5) can be positioned and retained. Retaining means are provided in the form of a screw 70 which can be screwed into a threaded screw hole .72 within the body of roller 20. Thus the surface 74 of a roller may be provided with a plurality of cutter holding means 66 for the cutters 42, 44, 46 of the invention.

In the preferred form of the invention the surface 74 of roller 20 is cylindrical with the cutter holder recesses 66 machined in. Bearers 76 are provided at either end of the roller 20'to space the cylindrical surface 74 away from anvil surface 48 so that cutting edges 56 of the cutters 42, 44, '46 can be positioned properly for the cutting operation. The proper position for the cutting edges 56 of the cutters 42,44, 46 is in contacting relationship with the anvil surface 48.

ln FlG. 6 of the drawings cutters 42d, 44d, 46d are shown with curved ends 56a at the ends of the cutting edges 56b where they otherwise would intersect to form right angles as shown in FIG. 4.

A cutter 42, 44, 46 with sharp right angle corners forming the ends of the cutting edges will have a tendency to spread the web material at the ends of the cut and cause a slight internal rupture or nick on the web at the end of the cut. When edges 56b are curved at their ends 56a, as in FIG. 6, an abrupt ending is avoided thereby making a clean cut of the web without rupture or nick.

Although the measurement is not critical, it has been found that a radius of approximately one thirty-second inch of rounding provides a suitable curve 56a at the ends of the cutting edges 56b. In all other respects the cutters 42d, 44d, 46d are similar to cutters 42, 44, 46 in construction and operation.

The bearers 76'are provided to separate the contacting areas between the rollers 20 and 22. This type of construction provides positive contact at the endsof the rollers while permitting a separation between the surfaces 74 and 48 of the rollers 20 and 22, respectively, to permit accurate adjustment of the cutting edges 56 and to provide constant loading forces on the bearings.

In the prior art steel-rule cutters were placed on cutter rollers and then run against anvil rollers in a spring bearing relationship so that the cutter edges would selfadjust themselves against the surface of the anvil roller, partly by spring action and partly by mashing the edges of the individual cutters. The construction of the invention'and the adjustment features provided by the bearers 76 and the arrangement ofthe cutter holding means 66, in combination with a plastic setting material 90,

makes provision for self-adjusting cutters in combination with rollers which act positively in cooperation with each other without springs and without mashing the cutter edges. In the present invention the cutters are aligned in exact position by the inherent construction of the device, including the self-adjusting feature described below.

The means for placing the cutters 42, 44, 46 in proper alignment comprises a cutter pocket 66 and a plastic setting material 90. The plastic setting material 90 may be an epoxy such as the type known as plasticsteel which can be applied during a soft phase and which then hardens to a solid state by setting after application. A plastic steel suitable for use in the invention'is available under the notation Type A Plastic Steel" from Devcon Products Company of Danvers, Massachusetts. 7

Reference'is now made to FIG. 5 of the drawings. In a preferred form of the invention the cutter holding means 66 is provided with a second wall 80. The wall 80 is spaced with relation to wall 68 so that a cutter 42, 44, 46 having been placed in position and retained by hand fastening a screw will provide a space 84 between its end 82 and wall 80. A quantity of setting material 90, such as the plastic-steel described hereinabove, is placed in the space 84 between wall and cutter end 82. The material might be set in space 84 either before or after the cutter 42, 44, 46 is placed in position. In the preferred form of the invention, the material is first placed in position and the cutter 42,44, 46 is then lightly hand fastened in place by means of screw 70. Small holes or recesses 86 may be provided in wall 68 so that the setting material 90 may have a further area within the pocket 66 of the roller 20 in which to grip. While the setting material 90 is still in a relatively soft condition the roller 20 is rotated completely around at least once so that each cutter.42, 44, 46 and its exposed cutting edge 56 is pressed against the surface 48 of the anvilto makethe proper self-adjustment for each individual edge 56.

It is desirable to have the cutting edge 56 of the cutters 42, 44, 46 extend slightly beyond the theoretical circumference 50 so that there will. be some pressure to enhance their cutting operation. This is accomplished by rotating the roller 20 to self-adjust the cutter edge after shim material 76a (indicated in exploded position in FIG. 3) has been placed between the circular surfaces of cutter roller bearer 76 and anvil roller bearer 76b. The shim 76a can be of any material appropriate for the purpose, preferably metal such as shim steel.

The cutter roller 20 is then allowed to stand until the epoxy 90 in each cutter holder 66 hardens, at which time all of the cutters 42, 44, 46 in roller are aligned an positioned to protrude slightly beyond the circumference of the bearers 76. The shim 76a is then removed and the roller 20 is ready for use. The screws 70 can then be tightened to maintain the setting of the cutters 42, 44, 46. i

The hardened setting material 90 within space 84 provides a substantially permanent base for resetting any particular cutter 42, 44, 46 when it is desired to present a new cutting edge 56. For example, when an edge 56 becomes dull a cutter 42, 44, 46 can be removed and placed-back after turning or' reversing in order to present a new sharp edge 56. The cutter 42, 44, 46 will be automatically aligned since it will fit against the hardened material 90 which has previously been adjusted as aforesaid. It is to 'be understood that the cutting edges 56 are comprised in end portions such as end 82 of the cutters 42 44, 46,- and in a square shape cutter there are four such end portions 82 each comprising two cutting edges 56. A through opening 9 is provided in each cutter for the screw 70.

The anvil surface 48 is preferably comprised in a roller such as roller 22 in which there are a plurality of flexible sleeves 100, preferably rubber, around a core 102. The roller 22also comprises a pair of hardened ends 76b concentric 'to journals 40 and positioned to be in alignment 'with the bearers 76 of the cutting roller 20. Between hardened ends 76b and overlying the flexible sleeves 100 are a number of hard sleeve segments, 106, preferably steel, which form the outer anvil surface 48. Thus there will be a series of separate ring-like anvil means 110, each comprising a hard cylindrical outer ring 106 and a flexible inner ringl00 surrounding the core 102 of the roller 22. In the preferred embodiment each row 60 or 62 or 64 of cutters will be provided with a cooperating anvil means 110 as shown in FIG. 3 of the drawings.

While preferred embodiments of the invention have been described, there are other forms which may come within the spirit and scope of the claims hereinbelow. For example, an anvil roller 22 having its outer hard sleeve elements 106 in the form of a single unseparated sleeve overlying the resilient sleeves 100 between the end bearer elements 76b, when made of a thin, hard, yet flexible material, such as blue spring steel, may also serve well as an anvil roller in combination with the cutter roller of the invention, and it is therefore desired that protection be afforded for all forms of the invention coming within the claims hereinbelow.

Wherefore, it is claimed:

1. A cutting roller comprising a main body portion including an axis and comprising cutters comprising cutting edges positioned substantially along-imaginary line elements comprised in the surface of an imaginary cylinder around said cutting roller, said elements being parallel to said axis, said cutting edges being arranged in rows defined by circles centered on said axis, with only one cutting edge positioned along any single element parallelto said axis in which said cutting edges comprise curved ends.

2. The cutting roller as claimed in claim 1, in combination with anvil surface means.

3. In the combination as claimed in claim 2, a roller body portion comprising a substantially cylindricalsurface, and bearer means positioned to space said cylindrical surface of said cutting roller body portion from v the anvil surface means.

4. A cutting roller comprising a main body portion including an axis and comprising cutters. comprising cutting edges positioned substantially along imaginary line elements comprised in the surface of an imaginary cylinder around said cutting roller, said elements being parallel to said axis, said cutting edges being in staggered arrangement in a plurality of rows defined by circles centered on said axis, with only one cutting edge positioned along any single element parallel to said axis, in combination with anvil surface means included in an anvil roller comprising a substantially cylindrical surface of hard material to cooperate with the cutters, said cutting roller main body portion comprising a sub stantially cylindrical surface, and said combination having bearer means positioned to space said cylindrical surface of said cutting roller main body portion from the anvil surface means, said anvil roller comprising a core surrounded by flexible sleeve means surrounded by hard sleeve means comprising the hard cylindrical surface.

5. The combination as claimed in claim 4, in which the cutters comprising cutting edges are held in cutter holding means positioned at the cylindrical surface of said cutting roller body portion with a cutting edge of each cutter extending from the surface of the roller body'portion and positioned in contacting relationship to the anvil surface means.

6. Acutting roller comprising a main body portion including an axis and comprising cutter holding means and cutters in said cutter holding means comprising at least one cutting edge extending from said cutter holding means and at least one cutter end means opposite said cutting edge positioned in said cutter holding means, said cutting edges being positioned substantially along imaginary line-elements comprised in the surface of an imaginary cylinder around said cutting roller, said elements being parallel to said axis of said main body portion, said cutting edges being arranged in rows defined by circles centered on said axis, with only one cutting edge positioned along any single element parallel to said axis, at least one of said cutter holding means comprising wall means in spaced facing relationship to said cutter end means and cutter positioning means comprising a setting material between said wall means and said cutter end means facing said wall means.

7. The cutting roller as claimed in claim 6 in combination with anvil means to cooperate with the cutters.

8. The combination as claimed in claim 7 which further comprises cutter retaining means.

9. The combination as claimed in claim 8, which comprises bearer means.

10. The cutting roller as claimed in claim 6, in which the cutters are rectangular.

11. The cutting roller as claimed in claim 6, in which the cutters are substantially square.

12. The combination as claimed in claim 9, in which bearer means are located at the ends of the cutting roller.

13. The combination as claimed in claim 4, in which the flexible sleeve means and the hard cylindrical sleeve means are positioned as a series of separate-ringlike anvil means concentric with said core, said ringlike anvil means being positioned to cooperate with said rows of cutters.

14. The cutting roller as claimed in claim 6, in which the cutter comprises at least one cutting edge comprising curved ends.

15. The cutting roller as claimed in claim 6, further comprising cutter retaining means.

16. The cutting roller as claimed in claim 15, in which the 'cutter retaining means are releasable.

17. The cutting roller as claimed in claim 16, in which at least one cutter comprises a first and a second end portion, with one of said end portions selectively set in a setting of setting material, whereby selective removal, reversal and replacement selectively sets the other end portion in set position against the setting material.

18. The cutting roller as claimed in claim 17, in which at least one of said first and second end portions comprises a pair of cutting edges.

19. The cutting roller as defined in claim 16, in which at least one cutter comprises a first end portion selectively set in setting material, and a second end portion including a first and a second cutting edge, with one of said cutting edges in cutting position; whereby removal, and reversal of said cutter, and replacement of said cutter with said first end portion in said set material will position the other cutting edge in cutting position.

,20. A cutting roller having a main body portion comprising at least one cutter to perform a cutting operation at a work surface, including cutter positioning means comprising a setting material, in combination with anvil roller means having work surface means on which to perform operations, said anvil roller means comprising a. core, a resilient sleeve around said core, and a hard sleeve around said resilient sleeve.

21. The combination as claimed in claim 20, in which the resilient sleeve means comprises a plurality of resilient sleeves fitted around its core beneath the hard sleeve means.

22. The combination as claimed in claim 21, in which the hard sleeve means comprises a relatively thin flexible material.

23. The combination as claimed in claim 21, in which the hard sleeve means comprises a plurality of hard sleeves set around the resilient sleeves forming a plurality of ring-like anvil means concentric with the core.

24. The combination as claimed in claim 20 in which at least one cutter is positioned in cutter positioning means with a cutting edge against the surface means of the anvil means prior to and after the setting of the setting material.

25. The cutting roller as claimed in claim 15, in which the cutters are provided with central openings through which holding screws are positioned. 

1. A cutting roller comprising a main body portion including an axis and comprising cutters comprising cutting edges positioned substantially along imaginary line elements comprised in the surface of an imaginary cylinder around said cutting roller, said elements being parallel to said axis, said cutting edges being arranged in rows defined by circles centered on said axis, with only one cutting edge positioned along any single element parallel to said axis in which said cutting edges comprise curved ends.
 2. The cutting roller as claimed in claim 1, in combination with anvil surface means.
 3. In the combination as claimed in claim 2, a roller body portion comprising a substantially cylindrical surface, and bearer means positioned to space said cylindrical surface of said cutting roller body portion from the anvil surface means.
 4. A cutting roller comprising a main body portion including an axis and comprising cutters comprising cutting edges positioned substantially along imaginary line elements comprised in the surface of an imaginary cylinder around said cutting roller, said elements being parallel to said axis, said cutting edges being in staggered arrangement in a plurality of rows defined by circles centered on said axis, with only one cutting edge positioned along any single element parallel to said axis, in combination with anvil surface means included in an anvil roller comprising a substantially cylindrical surface of hard material to cooperate with the cutters, said cutting roller main body portion comprising a substantially cylindrical surface, and said combination having bearer means positioned to space said cylindrical surface of said cutting roller main body portion from the anvil surface means, said anvil roller comprising a core surrounded by flexible sleeve means surrounded by hard sleeve means comprising the hard cylindrical surface.
 5. The combination as claimed in claim 4, in which the cutters comprising cutting edges are held in cutter holding means positioned at the cylindrical surface of said cutting roller body portion with a cutting edge of each cutter extending from the surface of the roller body portion and positioned in contacting relationship to the anvil surface means.
 6. A cutting roller comprising a main body portion including an axis and comprising cutter holding means and cutters in said cutter holding means comprising at least one cutting edge extending from said cutter holding means and at least one cutter end means opposite said cutting edge positioned in said cutter holdiNg means, said cutting edges being positioned substantially along imaginary line elements comprised in the surface of an imaginary cylinder around said cutting roller, said elements being parallel to said axis of said main body portion, said cutting edges being arranged in rows defined by circles centered on said axis, with only one cutting edge positioned along any single element parallel to said axis, at least one of said cutter holding means comprising wall means in spaced facing relationship to said cutter end means and cutter positioning means comprising a setting material between said wall means and said cutter end means facing said wall means.
 7. The cutting roller as claimed in claim 6 in combination with anvil means to cooperate with the cutters.
 8. The combination as claimed in claim 7 which further comprises cutter retaining means.
 9. The combination as claimed in claim 8, which comprises bearer means.
 10. The cutting roller as claimed in claim 6, in which the cutters are rectangular.
 11. The cutting roller as claimed in claim 6, in which the cutters are substantially square.
 12. The combination as claimed in claim 9, in which bearer means are located at the ends of the cutting roller.
 13. The combination as claimed in claim 4, in which the flexible sleeve means and the hard cylindrical sleeve means are positioned as a series of separate ring-like anvil means concentric with said core, said ring-like anvil means being positioned to cooperate with said rows of cutters.
 14. The cutting roller as claimed in claim 6, in which the cutter comprises at least one cutting edge comprising curved ends.
 15. The cutting roller as claimed in claim 6, further comprising cutter retaining means.
 16. The cutting roller as claimed in claim 15, in which the cutter retaining means are releasable.
 17. The cutting roller as claimed in claim 16, in which at least one cutter comprises a first and a second end portion, with one of said end portions selectively set in a setting of setting material, whereby selective removal, reversal and replacement selectively sets the other end portion in set position against the setting material.
 18. The cutting roller as claimed in claim 17, in which at least one of said first and second end portions comprises a pair of cutting edges.
 19. The cutting roller as defined in claim 16, in which at least one cutter comprises a first end portion selectively set in setting material, and a second end portion including a first and a second cutting edge, with one of said cutting edges in cutting position; whereby removal, and reversal of said cutter, and replacement of said cutter with said first end portion in said set material will position the other cutting edge in cutting position.
 20. A cutting roller having a main body portion comprising at least one cutter to perform a cutting operation at a work surface, including cutter positioning means comprising a setting material, in combination with anvil roller means having work surface means on which to perform operations, said anvil roller means comprising a core, a resilient sleeve around said core, and a hard sleeve around said resilient sleeve.
 21. The combination as claimed in claim 20, in which the resilient sleeve means comprises a plurality of resilient sleeves fitted around its core beneath the hard sleeve means.
 22. The combination as claimed in claim 21, in which the hard sleeve means comprises a relatively thin flexible material.
 23. The combination as claimed in claim 21, in which the hard sleeve means comprises a plurality of hard sleeves set around the resilient sleeves forming a plurality of ring-like anvil means concentric with the core.
 24. The combination as claimed in claim 20 in which at least one cutter is positioned in cutter positioning means with a cutting edge against the surface means of the anvil means prior to and after the setting of the setting material.
 25. The cutting roller as claimed in claim 15, in which the cutters Are provided with central openings through which holding screws are positioned. 